Register eMMC RPMB partition with the RPMB subsystem and provide an implementation for the RPMB access operations abstracting the actual multi step process.
Add a callback to extract the needed device information at registration to avoid accessing the struct mmc_card at a later stage as we're not holding a reference counter for this struct.
Taking the needed reference to md->disk in mmc_blk_alloc_rpmb_part() instead of in mmc_rpmb_chrdev_open(). This is needed by the route_frames() function pointer in struct rpmb_ops.
Signed-off-by: Tomas Winkler tomas.winkler@intel.com Signed-off-by: Alexander Usyskin alexander.usyskin@intel.com Signed-off-by: Jens Wiklander jens.wiklander@linaro.org Tested-by: Manuel Traut manut@mecka.net Reviewed-by: Linus Walleij linus.walleij@linaro.org --- drivers/mmc/core/block.c | 241 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 239 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 2c9963248fcb..ec8b13b9be12 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -33,6 +33,7 @@ #include <linux/cdev.h> #include <linux/mutex.h> #include <linux/scatterlist.h> +#include <linux/string.h> #include <linux/string_helpers.h> #include <linux/delay.h> #include <linux/capability.h> @@ -40,6 +41,7 @@ #include <linux/pm_runtime.h> #include <linux/idr.h> #include <linux/debugfs.h> +#include <linux/rpmb.h>
#include <linux/mmc/ioctl.h> #include <linux/mmc/card.h> @@ -76,6 +78,48 @@ MODULE_ALIAS("mmc:block"); #define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16) #define MMC_EXTRACT_VALUE_FROM_ARG(x) ((x & 0x0000FF00) >> 8)
+/** + * struct rpmb_frame - rpmb frame as defined by eMMC 5.1 (JESD84-B51) + * + * @stuff : stuff bytes + * @key_mac : The authentication key or the message authentication + * code (MAC) depending on the request/response type. + * The MAC will be delivered in the last (or the only) + * block of data. + * @data : Data to be written or read by signed access. + * @nonce : Random number generated by the host for the requests + * and copied to the response by the RPMB engine. + * @write_counter: Counter value for the total amount of the successful + * authenticated data write requests made by the host. + * @addr : Address of the data to be programmed to or read + * from the RPMB. Address is the serial number of + * the accessed block (half sector 256B). + * @block_count : Number of blocks (half sectors, 256B) requested to be + * read/programmed. + * @result : Includes information about the status of the write counter + * (valid, expired) and result of the access made to the RPMB. + * @req_resp : Defines the type of request and response to/from the memory. + * + * The stuff bytes and big-endian properties are modeled to fit to the spec. + */ +struct rpmb_frame { + u8 stuff[196]; + u8 key_mac[32]; + u8 data[256]; + u8 nonce[16]; + __be32 write_counter; + __be16 addr; + __be16 block_count; + __be16 result; + __be16 req_resp; +} __packed; + +#define RPMB_PROGRAM_KEY 0x1 /* Program RPMB Authentication Key */ +#define RPMB_GET_WRITE_COUNTER 0x2 /* Read RPMB write counter */ +#define RPMB_WRITE_DATA 0x3 /* Write data to RPMB partition */ +#define RPMB_READ_DATA 0x4 /* Read data from RPMB partition */ +#define RPMB_RESULT_READ 0x5 /* Read result request (Internal) */ + static DEFINE_MUTEX(block_mutex);
/* @@ -163,6 +207,7 @@ struct mmc_rpmb_data { int id; unsigned int part_index; struct mmc_blk_data *md; + struct rpmb_dev *rdev; struct list_head node; };
@@ -2670,7 +2715,6 @@ static int mmc_rpmb_chrdev_open(struct inode *inode, struct file *filp)
get_device(&rpmb->dev); filp->private_data = rpmb; - mmc_blk_get(rpmb->md->disk);
return nonseekable_open(inode, filp); } @@ -2680,7 +2724,6 @@ static int mmc_rpmb_chrdev_release(struct inode *inode, struct file *filp) struct mmc_rpmb_data *rpmb = container_of(inode->i_cdev, struct mmc_rpmb_data, chrdev);
- mmc_blk_put(rpmb->md); put_device(&rpmb->dev);
return 0; @@ -2701,10 +2744,165 @@ static void mmc_blk_rpmb_device_release(struct device *dev) { struct mmc_rpmb_data *rpmb = dev_get_drvdata(dev);
+ rpmb_dev_unregister(rpmb->rdev); + mmc_blk_put(rpmb->md); ida_free(&mmc_rpmb_ida, rpmb->id); kfree(rpmb); }
+static void free_idata(struct mmc_blk_ioc_data **idata, unsigned int cmd_count) +{ + unsigned int n; + + for (n = 0; n < cmd_count; n++) + kfree(idata[n]); + kfree(idata); +} + +static struct mmc_blk_ioc_data **alloc_idata(struct mmc_rpmb_data *rpmb, + unsigned int cmd_count) +{ + struct mmc_blk_ioc_data **idata; + unsigned int n; + + idata = kcalloc(cmd_count, sizeof(*idata), GFP_KERNEL); + if (!idata) + return NULL; + + for (n = 0; n < cmd_count; n++) { + idata[n] = kcalloc(1, sizeof(**idata), GFP_KERNEL); + if (!idata[n]) { + free_idata(idata, n); + return NULL; + } + idata[n]->rpmb = rpmb; + } + + return idata; +} + +static void set_idata(struct mmc_blk_ioc_data *idata, u32 opcode, + int write_flag, u8 *buf, unsigned int buf_bytes) +{ + /* + * The size of an RPMB frame must match what's expected by the + * hardware. + */ + BUILD_BUG_ON(sizeof(struct rpmb_frame) != 512); + + idata->ic.opcode = opcode; + idata->ic.flags = MMC_RSP_R1 | MMC_CMD_ADTC; + idata->ic.write_flag = write_flag; + idata->ic.blksz = sizeof(struct rpmb_frame); + idata->ic.blocks = buf_bytes / idata->ic.blksz; + idata->buf = buf; + idata->buf_bytes = buf_bytes; +} + +static int mmc_route_rpmb_frames(struct device *dev, u8 *req, + unsigned int req_len, u8 *resp, + unsigned int resp_len) +{ + struct rpmb_frame *frm = (struct rpmb_frame *)req; + struct mmc_rpmb_data *rpmb = dev_get_drvdata(dev); + struct mmc_blk_data *md = rpmb->md; + struct mmc_blk_ioc_data **idata; + struct mmc_queue_req *mq_rq; + unsigned int cmd_count; + struct request *rq; + u16 req_type; + bool write; + int ret; + + if (IS_ERR(md->queue.card)) + return PTR_ERR(md->queue.card); + + if (req_len < sizeof(*frm)) + return -EINVAL; + + req_type = be16_to_cpu(frm->req_resp); + switch (req_type) { + case RPMB_PROGRAM_KEY: + if (req_len != sizeof(struct rpmb_frame) || + resp_len != sizeof(struct rpmb_frame)) + return -EINVAL; + write = true; + break; + case RPMB_GET_WRITE_COUNTER: + if (req_len != sizeof(struct rpmb_frame) || + resp_len != sizeof(struct rpmb_frame)) + return -EINVAL; + write = false; + break; + case RPMB_WRITE_DATA: + if (req_len % sizeof(struct rpmb_frame) || + resp_len != sizeof(struct rpmb_frame)) + return -EINVAL; + write = true; + break; + case RPMB_READ_DATA: + if (req_len != sizeof(struct rpmb_frame) || + resp_len % sizeof(struct rpmb_frame)) + return -EINVAL; + write = false; + break; + default: + return -EINVAL; + } + + if (write) + cmd_count = 3; + else + cmd_count = 2; + + idata = alloc_idata(rpmb, cmd_count); + if (!idata) + return -ENOMEM; + + if (write) { + struct rpmb_frame *frm = (struct rpmb_frame *)resp; + + /* Send write request frame(s) */ + set_idata(idata[0], MMC_WRITE_MULTIPLE_BLOCK, + 1 | MMC_CMD23_ARG_REL_WR, req, req_len); + + /* Send result request frame */ + memset(frm, 0, sizeof(*frm)); + frm->req_resp = cpu_to_be16(RPMB_RESULT_READ); + set_idata(idata[1], MMC_WRITE_MULTIPLE_BLOCK, 1, resp, + resp_len); + + /* Read response frame */ + set_idata(idata[2], MMC_READ_MULTIPLE_BLOCK, 0, resp, resp_len); + } else { + /* Send write request frame(s) */ + set_idata(idata[0], MMC_WRITE_MULTIPLE_BLOCK, 1, req, req_len); + + /* Read response frame */ + set_idata(idata[1], MMC_READ_MULTIPLE_BLOCK, 0, resp, resp_len); + } + + rq = blk_mq_alloc_request(md->queue.queue, REQ_OP_DRV_OUT, 0); + if (IS_ERR(rq)) { + ret = PTR_ERR(rq); + goto out; + } + + mq_rq = req_to_mmc_queue_req(rq); + mq_rq->drv_op = MMC_DRV_OP_IOCTL_RPMB; + mq_rq->drv_op_result = -EIO; + mq_rq->drv_op_data = idata; + mq_rq->ioc_count = cmd_count; + blk_execute_rq(rq, false); + ret = req_to_mmc_queue_req(rq)->drv_op_result; + + blk_mq_free_request(rq); + +out: + free_idata(idata, cmd_count); + return ret; +} + static int mmc_blk_alloc_rpmb_part(struct mmc_card *card, struct mmc_blk_data *md, unsigned int part_index, @@ -2739,6 +2937,7 @@ static int mmc_blk_alloc_rpmb_part(struct mmc_card *card, rpmb->dev.release = mmc_blk_rpmb_device_release; device_initialize(&rpmb->dev); dev_set_drvdata(&rpmb->dev, rpmb); + mmc_blk_get(md->disk); rpmb->md = md;
cdev_init(&rpmb->chrdev, &mmc_rpmb_fileops); @@ -3000,6 +3199,42 @@ static void mmc_blk_remove_debugfs(struct mmc_card *card,
#endif /* CONFIG_DEBUG_FS */
+static void mmc_blk_rpmb_add(struct mmc_card *card) +{ + struct mmc_blk_data *md = dev_get_drvdata(&card->dev); + struct mmc_rpmb_data *rpmb; + struct rpmb_dev *rdev; + unsigned int n; + u32 cid[4]; + struct rpmb_descr descr = { + .type = RPMB_TYPE_EMMC, + .route_frames = mmc_route_rpmb_frames, + .reliable_wr_count = card->ext_csd.enhanced_rpmb_supported ? + 2 : 32, + .capacity = card->ext_csd.raw_rpmb_size_mult, + .dev_id = (void *)cid, + .dev_id_len = sizeof(cid), + }; + + /* + * Provice CID as an octet array. The CID needs to be interpreted + * when used as input to derive the RPMB key since some fields + * will change due to firmware updates. + */ + for (n = 0; n < 4; n++) + cid[n] = be32_to_cpu(card->raw_cid[n]); + + list_for_each_entry(rpmb, &md->rpmbs, node) { + rdev = rpmb_dev_register(&rpmb->dev, &descr); + if (IS_ERR(rdev)) { + pr_warn("%s: could not register RPMB device\n", + dev_name(&rpmb->dev)); + continue; + } + rpmb->rdev = rdev; + } +} + static int mmc_blk_probe(struct mmc_card *card) { struct mmc_blk_data *md; @@ -3045,6 +3280,8 @@ static int mmc_blk_probe(struct mmc_card *card) pm_runtime_enable(&card->dev); }
+ mmc_blk_rpmb_add(card); + return 0;
out: